Light emitting modules including light emitting elements like a Light Emitting Diode (LED) are broadly applied to indoor, outdoor, stationary, and movable display devices, indication lamps, various switches, signaling devices, and optical devices like a commonly used lighting device. Among such light emitting modules that include LEDs, a light transmissive emitting module that has multiple LEDs disposed between two light transmissive substrates is known as a suitable device for display devices and indication lamps that display various letter strings, geometric figures, and patterns.
By applying flexible substrates formed of a light transmissive resin as the light transmissive substrates, a constraint for an attaching surface for the light emitting module as the display device and the indication lamp is eased, and thus the convenience and availability of the light transmissive emitting module are improved.
A light transmissive emitting module employs a structure that has multiple LED chips disposed between a pair of light transmissive insulation substrates each including a conductive circuitry layer. Each of the multiple LED chips includes a pair of electrodes, and the electrodes are electrically connected to the conductive circuitry layer formed on the light transmissive insulation substrate. A flexible light transmissive resin is filled in between the pair of light transmissive insulation substrates. The LED chip is held by the light transmissive resin with the electrodes being in contact with the corresponding pieces of the conductive circuitry layer.
In the above light emitting module, an improvement for the connection reliability between the electrode of the LED chip and the conductive circuitry layer is desired.